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United States Patent | 5,614,734 |
Guido | March 25, 1997 |
An LED structure including a distributed Bragg reflector having multiple periods, each period including at least a first layer made of a first indirect band gap material and a second layer made of a second indirect band gap material, the first band gap material having a higher index of refraction than the second indirect band gap material; and a light emitting diode formed on top of the distributed Bragg reflector, the light emitting diode having a top layer and a bottom layer, the bottom layer being proximate to the distributed Bragg reflector.
Inventors: | Guido; Louis J. (Trumbull, CT) |
Assignee: | Yale University (New Haven, CT) |
Appl. No.: | 404592 |
Filed: | March 15, 1995 |
Current U.S. Class: | 257/94; 257/95; 257/E27.121; 257/E33.027; 257/E33.068; 257/E33.07 |
Intern'l Class: | H01L 033/00 |
Field of Search: | 257/94,95 |
4378255 | Mar., 1983 | Holonyak, Jr. et al. | 148/1. |
4439782 | Mar., 1984 | Holonyak, Jr. | 357/17. |
4511408 | Apr., 1985 | Holonyak, Jr. | 148/1. |
4594603 | Jun., 1986 | Holonyak, Jr. | 357/16. |
4639275 | Jan., 1987 | Holonyak, Jr. | 148/1. |
5048035 | Sep., 1991 | Sugawara et al. | 372/45. |
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